Method for increasing the tensile strength of yarns



June 23, 1931. F. J. H'oxlE ET AL `METHOD FOR INCREASING THE TENSILE STRENGTH OF YARNS Filed March 19 1926 ngz i ar

ATTORNEY Patented June `23, 1931 UNITED STATES PATENT `oFFIcl:

FREDERICK ,J'. HOXIE, OF PHENIX, RHODE ISLAND, AND ASHTON M. TENNEY, OF NEW ROCHELLE, NEW YORK, ASSIGNORS, BY DIRECT AND MESNE ASSIGNMENTS, OF ONE-HALF T0 WELLINGTON, SEARS & COMPANY, OENEW YORK, N. Y., A FIRM CON- SISTING OF HARRY L. BAILEY, NORMAN S. HOPE, JOHN H. BENNETT,'A.ND CHARLES 0. RICHARDSON, AND ONE-HALF TO WARWICK MILLS, OF WEST WARWICK, RHODE ISLAND, A CORPORATION OF RHODE ISLAND METHOD FOR INCREASING THE TENSILE STRENGTH OF YARNS Application filed 'March 19, 192.6. Serial No. 95,978.

vOur present invention relates to animprovement in methods for increasing the tensile strength of yarns and textile threads of a similar nature, such as will bc hereinafter disclosed. y

This improvelnent is also directed to the provision of apparatus whereby the hereinafter to be'outlined methods of treatment are carried out, such illustration beingin a 0 more or less diagrammatic manner.

One of the main advantages of our invention relates to the manner in which yarns utilized thereafter 1n looms for weaving, and

whereby the tensile strength of such yarns may be increased so. as to prevent breakage during the Weaving process.

Another advantage of our invention lies in the fact that after the treatment has been carried out on yarns and woven into fabrics, the results of the treatment may be removed by the mere process of washing, thereby leaving the fabric in a condition that it originally would have been had the yarn been untreated, with the exception that the yarn has been Woven into a fabric unbroken and unstretched, and therefore without any defects in this respect.

Another advantage of our invention resides in the lnanner in which the yarn may be treated in bulk, or in large masses, so that the cost thereof is greatly reduced.

These and other capabilities will be ascer- J 'tained as the description herein proceeds and it is understood that modifications may be madein the process and apparatusfherein outlined without violating the scope 0f the invention as herein disclosed.

While our invention is directed to certain classes of yarns, which, are normally very weak, it is more especially directed to 'the treatment of artificial silk known in the trade, at present as rayon, which, as is well known, lacks tensile strength in the yarn, and

this failing very often creates difficulties in the weaving thereof owing to the breakage or stretching of the yarn, which has not been, up till now, controlled. l

For the purpose of strengthening the yarn without affecting its pliability, prior to the weaving thereof into desired fabrics, in order to do away with breakage and to prevent the stretching of the yarn during Weaving, thereby creating what is known as shiners in the completed fabric, we have ascertained that rayon, being insoluble and non-absorbent in its nature, may be treated in the skein with a coating of water-soluble quick-drying size or adhesive dressing materials, which are sufficiently flexible when dried to permit of Weaving. One satisfactory material is gelatine, which, after the yarn has been coated, may be sufficiently dried and manipulated in such a manner as to permit the mass of threads within the skein to be flufl'ed and kept individually separated, thereby leaving the skeins in condition to be wound upon bobbins, the threads of said skeins being separate, one from the other, notwithstanding the fact that they Were treated and dried in a skein mass.

A further step during the process is the provision cf means whereby after the gelatinous coating has been placed upon the yarn it is possible t0 evenly distribute the coating upon the thread to any predetermined thickness. This is the deciding factor of what the added tensile strength of the thread may be and also its residual flexibility, sufficient for weaving purposes.

Our invention also contemplates the further provision of a step wherein the gelatine-treated yarn, after such treatment, including the control of the thickness of the coating thereon, may be rapidly dried by artificial heating means whereby the moisture content of the hygroscopic coating may be rapidly extracted therefrom and during such extraction, the reaction thereof Willl be conducive to the permanent separation of the threads forming the skein, as such, and prevent their adhering, thereby to form a mass.

In the accompanying drawings:

Fig. l is a sectional View of a circular form of machine, taken on the section lines l-l, v

section a structural apparatus in which our Aprocess is carried out and in general comprises a non-rotatable frame' casing, generally denoted by 1, having side walls 2 and a base` flange 3 which in turn is suitabl and immovably affixed to a base plate B. t the upper end of the frame 1 is located a sheet metal pan or housing, generally denoted by 4, which has an annular upstanding edge 5 and a sloped bottom 6 which is provided with an upt-urned inner flange 7, the function of which will be later described. i

The upper pan 4 is provided with a fairly tight closing cover 8, which is -removable therefrom upon occasion. A

lAt the center of thev housing there is provided a bearin 9 in which is mounted a revolvable spin le 10, at the bottom end of which lis suitably aflixed thereto, for driving,

a bevel gear 11 which in turn meshes with a bevelpinion 12 which is driven at suitable speeds by an electric motor M which is suitmounted to the base 1 as shown.-v he upper end of the spindle carries on its upper flange 13, 'a revolvable pan or cen'- trifuge 14, the sides of which are preferably sloping or flaredoutwardly as shown. At predetermined intervals as at 15, Figs.

"1, and 2, there are mounted to the bottom 0f the pan, any desired number of fixed skein pegs 15 and in radial alinement therewith l and near the center thereof, there are vmounted anequal number of adjustable skein pegs 16, these being set in gibways 17, so that a the pegs 16 may be adjustably set to suit the length of the skeins of y'arn 18, which are `mounted on said pegs 15 and 16, 'as shown in Fig. 1. In actual practice either one or both of these paired pegs may be adjustable 'for the purpose of taking up slack inthe skein and holding the skeins rigidly in'desired ra-l dial position in order to meet theA subsequent treatments and the later 'centrifugal action given, as will be later described.

i At the lower end, and preferablypwithin thebase 1, are located two reservoirs Gr and O, one of which G, carries within it a liquid solution of gelatine or any equivalent coating material that may be found suitable for the purpose. The opposite reservoir O is filled with a heatable material, such as mineral oil, of suitably high boiling point.

Under the oil reservoir O means are pro-v vided, such as a multiple gas burner H wheretherefor, and at the pump outlet ends are connected to internal ducts T, the outlets of which end within the, interior of the centrifuge 14 as at U, Fig. 1. AThese upstanding,

fixed ducts T-U are supported within the stationary spindle V which runs through the center of the spindle 10, and which is rigidly mounted upon the base B.

On opposite sides of the housing 1 are provided drain pipes W suitably mounted to receive thedrainage of their respective fluids,

as will be later described, whereby the said' fluids may be conducted back to their respective reservoirs and these ducts are controlled by'hand valves or other suitable means.` l

In order to carry out ourherei'n process, a plurality of skeins 18 are mounted upon the skein pegs 15, 16 which pegs are adjusted to hold the skeins rigidly in a, preferably, radial position to the axis of the centrifuge. v

The cover 8 is thereupon closed and the switch for starting the motor E, forlpumping gelatine, is then closed. This causes the centrifuge 14 to becomelled with liquid gelatine from the reservoir. G. The gelatine pump is stopped when a predetermined amount ofgelatine has been provided in the ioo centrifuge 14. The motor M is started, and

this causesthe centrifuge 14 to rotate Iat high speed and discharge all of the excess gelatine to be thrown into the drain pan 4, the hand valve X controlling the drainage of the gelatine back to the reservoir VGr is opened and the excess gelatine is thereafter caused to f low back into said reservoir for reuse. The centrifuge 14 may be revolved until all excess gelatine has been removed fromrthe skeins leaving them coated to any desired degree with a thin external coating upon the threads thereof, thereafter the gelatine drain pipe is closed, the motor M is stopped, and the motor E controlling the heated mineral oil from the reservoir O is then caused to pump the heated oil, into the centrifuge, until the centrifuge 14 is. filled and covers the skeins.

The flbw of hot oil is then stopped, the mo- 'tor M started and the centrifuge again re- After the foregoing described operation,-

the motor M- is stopped, the oil hand valve X f thereon, depending on the amount of centrifugal action they receive, this being under control.

Thereafter, upon the introduction of the hot oil, a peculiar phenomenon takes place, that is to say, that when the oil which may be heated to, not in excess of 250 'degrees F.' is

introduced upon the skeins, the heat thereof' causes an immediate change of the moisture content of the skeins into steam and this action, .while substantially instantaneous, causes the threads of the skein to become violently separated and fluffed away from one another at or about whichpoint the centrifuge is started and the excess hot oil is driven off and strands of the skein kept separated by the centrifugal action of the rotating centrifuge.

The gelatine coating upon the strands has in the meantime become thoroughly dried due to the heated oil and the skeins are thereafter removed in a flexible, pliable, condition having a dried coat of gelatine thereon which 'increases the tensile strength of the said threads without appreciably changing the texture or workable condition and with a thin coating of oil thereon which rather favors the later operation of weaving into fabrics.

After the ra on, so strengthened, has been woven into a abric, the fabric may then be treated in a hot water bath and all of the oil and gelatine thereafter removed, leaving the fabric in a clean condition and Without the customary defects which have heretofore been met with when rayon has been woven without treatment, as set forth above. Of course the coated strands can be lsold in skein form to Weavers.

We do not desire to be limited to the treatment of yarns in the skein, nor to treating the yarns with gelatine only, as we have ascertained that there are other size or adhesive dressing materials such as gums or their equivalents, albumens, starch, dextrin, or glucose that may be used which answer the purpose fully. It is to be further understood that we are not limited to mineral oil as the heating Huid. Any oil that Will not harm the artificial silk or coating is suitable.

Hot oil may be arrangedto flow cont-inuously into the centrifuge while the centrifuge is slowly revolving thereby making the action substantially continuous and without de- 1. The process of coating yarns in the skein for increasing the tensile strength thereof which consists in immersing the yarn 1n an aqueous solution of gelatine, subjecting said yarn to whirling, then immersing said yarn in a heated oil'the temperature of which is above the evaporating point of the water in said gelatine solution, to `vaporize said water, then whirling the yarn to remove the heated oil. y

2. The process of treating yai'ns'for increasing the` tensile strength thereof which consists in immersing the yarn in a solution of gelatine, to coat the same, then treating the said yarn by whirling to remove the excess gelatine, then immersing said yarn in a heated oil the temperature of which is above the evaporating point' of the solvent of said gelatine, to evaporate said solvent, then whirling the yarn to remove the heated oil.

3. The process of increasing the tensile strength of rayon which consists in treating skeins of rayon with a gelatine solution, drying said gelatine by a heated oil to a point which will remove, by evaporation, the solvent of said gelatine, leaving the gelatine in a dry condition and as a coating upon said rayon, subjecting the rayon skein to a whirling action during such treatment thereby to remove the excess gelatine and oil and thereby to fluff the rayon skein so that the individual threads of rayon are dried and kept separate one from' another in the skein mass.

4. The process of treating rayon threads in a. skein to increase the tensile strength thereof which consists in, first, causing an immersion of the said threads in liquid water soluble gelatine, whirling the same to remove the excess of said gelatine, then causing an immersion of the rayon skein in a bath of Vheated oil to cause rapid evaporation ofthe solvent of said gelatine, to dry the same d-uring which action the solvent is violently dissipated from the said gelatine and through the vapor caused thereby, to cause the in-l dividual threads of the skein, as treated, to

become separated one from the other and to then Whirl the said skein thereby driving off all the excess of the oil and completing the separation of the threads in the skein, through such centrifugal action.

5. The process of treating rayon threads to increase the tensile strength thereof which consists in, first, causing an immersion of the said threads in a gelatine solution, whirling the same toremove the excess of said gelatine and to coat the threads, then causing-an immersion of the threads in a bath of heated simultaneously subjecting` said skein to centrifugal action and heated numeral oil whereby ea; h yarn thread is separately dried.

v7. A v'process for increasing the tensilef strength'oi yarns which consists in coating a yarn skein with a water-soluble, rapidly drying adhesive sizing, and vsimultaneously subjecting ,said skein to heatedmineral -oil and'rotation whereby each yarn thread is individually dried.

8. A process of increasing the tensile strength of threads, which includes the steps of treating the thread by immersion in a water soluble adhesive sizing adapted to strengthen said thread for weaving of said thread info a fabric, then subjecting the thread to whirling action to remove the ex'- 1 cess sizing therefrom leaving a strengthening coating on sald thread, immersing sald coated thread in heated oil at a temperature abovethe evaporating point of the sizing solvent, and then subjecting the-thread to further whirling action whereby excess oil is removed and said thread is 'left with-said strengthening coating thereby rendering' it suitable for weaving into fabric.

-9. A process of increasing the tensile strength -of threads which includes'the steps tine whereby weaving of said threads is facilitated. I

12. A process for increasing the tensile strength of yarns, which consists in coating a yarn skein withan aqueous solution of a vsuitable 'adhesive dressing adapted to strengthen the yarn, then removing the excess of said dressing solution and then simultaneously drying said skein by means of a non-aqueous fluid having a sufliciently high .temperature and centrifugally treating said skein to separate the yarn threads in the skein from one another.

13. A. process for strengthening rayon threads'of 10W tensile strength, which consists in coating said threads with gelatine by immersing said threads in an aqueuous gelatine solution and then evaporating the Water of the solution by means ofl a nonaqueous Huid having a suitable temperature and, while said evaporating action is pro-. gressing, subjecting the threads to a ce'ntrifugal action.

Signed at New York, in the county of New York and State of New York, this- 18th day of March, A. D. 1926.

- FREDERICK J. ioXIE.

ASHTON M. TENNEY.

of treating the thread byimmersion in a gelatine solution, subjecting the thread toa whirling action thereby leaving a gelatine coating on said thread,'adapted to strengthen saidthread when said threadisbeing woven into fabric, immersing said gelatine coated thread in heated oil to remove the -Water in said gelatine, and then subjecting the thread to whirling actionto remove excess oil and dry said coatedthread. j v

10. A v-process for strengthening rayon threads of low tensile strength'which con- L sists in subjecting the threads to a gelatine solution, and 'then simultaneously subjecting said threads to centrifugal action andV heated mineral oil whereby the coating on each thread individually is dried.

11. As a new product, applicable for thev weaving of fabric, a skein of yarn, the threads of which are normally of low tensile strength,

coated with gelatine onfeach of said threads whereby the tensile strength of said'threads is increased and a ilmof oil on .said gelaico 

